/*
* LMIO 2019 Tax Evasion
* Main Idea : Euler tour, binary search the answer
* If there's a coin at depth d, it can only climb to
* floor((d - 1) / 2), as Just will get caught afterwards
* So we can build an euler tour, coin X can only stay at
* a range L to R
* Binary search the answer: if a is a candidate answer,
* all coins should have depth at least a - 1
* Check if >= a possible using greedy
*/
#include <iostream>
#include <vector>
#include <queue>
using namespace std;
int n, m, timer;
int par[18][200005], depth[200005], lf[200005], rg[200005];
bool is_coin[200005];
vector<int> adj[200005], que[200005], order;
void euler_tour(int nw){
order.push_back(nw);
lf[nw] = timer ++;
for(int nx : adj[nw])
euler_tour(nx);
rg[nw] = timer;
}
int anc(int nw, int dp){
for(int i = 17; i >= 0; i --)
if(dp & (1 << i)) nw = par[i][nw];
return nw;
}
int main(){
ios_base::sync_with_stdio(0);
cin.tie(0); cout.tie(0);
cin >> n >> m;
for(int p, i = 2; i <= n; i ++){
cin >> p;
par[0][i] = p;
depth[i] = depth[p] + 1;
adj[p].push_back(i);
}
for(int i = 1; i < 18; i ++) for(int j = 1; j <= n; j ++)
par[i][j] = par[i - 1][par[i - 1][j]];
for(int p, i = 0; i < m; i ++){
cin >> p;
is_coin[p] = true;
}
euler_tour(1);
for(int i = 1; i <= n; i ++) if(is_coin[i]){
int up = anc(i, (depth[i] - 1) / 2);
que[lf[up]].push_back(rg[up]);
}
int res = 0;
for(int l = 0, r = n, md; l <= r; ){
md = (l + r) / 2;
priority_queue<int, vector<int>, greater<int> > pq;
bool can = true;
for(int i = 0; i < n && can; i ++){
for(int j : que[i]) pq.push(j);
if(depth[order[i]] >= md && !pq.empty()){
int nw = pq.top(); pq.pop();
if(nw <= i) can = false;
}
}
if(!pq.empty()) can = false;
if(can){
res = md; l = md + 1;
}else{
r = md - 1;
}
}
cout << res + 1 << endl;
return 0;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
6 ms |
9856 KB |
Output is correct |
2 |
Correct |
5 ms |
9856 KB |
Output is correct |
3 |
Correct |
8 ms |
10752 KB |
Output is correct |
4 |
Correct |
9 ms |
10752 KB |
Output is correct |
5 |
Correct |
8 ms |
10752 KB |
Output is correct |
6 |
Correct |
73 ms |
42732 KB |
Output is correct |
7 |
Correct |
77 ms |
42732 KB |
Output is correct |
8 |
Correct |
7 ms |
10752 KB |
Output is correct |
9 |
Correct |
184 ms |
47304 KB |
Output is correct |
10 |
Correct |
217 ms |
47580 KB |
Output is correct |
11 |
Correct |
146 ms |
45272 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
6 ms |
9856 KB |
Output is correct |
2 |
Correct |
7 ms |
10496 KB |
Output is correct |
3 |
Correct |
6 ms |
10496 KB |
Output is correct |
4 |
Correct |
7 ms |
10368 KB |
Output is correct |
5 |
Correct |
7 ms |
10496 KB |
Output is correct |
6 |
Correct |
7 ms |
10368 KB |
Output is correct |
7 |
Correct |
73 ms |
42732 KB |
Output is correct |
8 |
Correct |
77 ms |
42732 KB |
Output is correct |
9 |
Correct |
7 ms |
10752 KB |
Output is correct |
10 |
Correct |
61 ms |
34884 KB |
Output is correct |
11 |
Correct |
61 ms |
34984 KB |
Output is correct |
12 |
Correct |
77 ms |
29836 KB |
Output is correct |
13 |
Correct |
70 ms |
36204 KB |
Output is correct |
14 |
Correct |
66 ms |
30316 KB |
Output is correct |
15 |
Correct |
71 ms |
29936 KB |
Output is correct |
16 |
Correct |
72 ms |
36204 KB |
Output is correct |
17 |
Correct |
98 ms |
30576 KB |
Output is correct |
18 |
Correct |
69 ms |
39152 KB |
Output is correct |
19 |
Correct |
69 ms |
34160 KB |
Output is correct |
20 |
Correct |
66 ms |
33780 KB |
Output is correct |
21 |
Correct |
72 ms |
33648 KB |
Output is correct |
22 |
Correct |
75 ms |
33776 KB |
Output is correct |
23 |
Correct |
69 ms |
33136 KB |
Output is correct |
24 |
Correct |
65 ms |
33524 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
6 ms |
9856 KB |
Output is correct |
2 |
Correct |
6 ms |
9856 KB |
Output is correct |
3 |
Correct |
5 ms |
9856 KB |
Output is correct |
4 |
Correct |
6 ms |
9856 KB |
Output is correct |
5 |
Correct |
6 ms |
9856 KB |
Output is correct |
6 |
Correct |
7 ms |
10496 KB |
Output is correct |
7 |
Correct |
7 ms |
10496 KB |
Output is correct |
8 |
Correct |
8 ms |
10496 KB |
Output is correct |
9 |
Correct |
10 ms |
10368 KB |
Output is correct |
10 |
Correct |
10 ms |
10368 KB |
Output is correct |
11 |
Correct |
10 ms |
10496 KB |
Output is correct |
12 |
Correct |
7 ms |
10368 KB |
Output is correct |
13 |
Correct |
9 ms |
10496 KB |
Output is correct |
14 |
Correct |
7 ms |
10368 KB |
Output is correct |
15 |
Correct |
8 ms |
10624 KB |
Output is correct |
16 |
Correct |
9 ms |
10624 KB |
Output is correct |
17 |
Correct |
8 ms |
10496 KB |
Output is correct |
18 |
Correct |
11 ms |
10624 KB |
Output is correct |
19 |
Correct |
9 ms |
10496 KB |
Output is correct |
20 |
Correct |
11 ms |
10368 KB |
Output is correct |
21 |
Correct |
8 ms |
10368 KB |
Output is correct |
22 |
Correct |
6 ms |
9856 KB |
Output is correct |
23 |
Correct |
5 ms |
9856 KB |
Output is correct |
24 |
Correct |
8 ms |
10752 KB |
Output is correct |
25 |
Correct |
9 ms |
10752 KB |
Output is correct |
26 |
Correct |
8 ms |
10752 KB |
Output is correct |
27 |
Correct |
6 ms |
9856 KB |
Output is correct |
28 |
Correct |
7 ms |
10496 KB |
Output is correct |
29 |
Correct |
6 ms |
10496 KB |
Output is correct |
30 |
Correct |
7 ms |
10368 KB |
Output is correct |
31 |
Correct |
7 ms |
10496 KB |
Output is correct |
32 |
Correct |
7 ms |
10368 KB |
Output is correct |
33 |
Correct |
7 ms |
10752 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
6 ms |
9856 KB |
Output is correct |
2 |
Correct |
6 ms |
9856 KB |
Output is correct |
3 |
Correct |
5 ms |
9856 KB |
Output is correct |
4 |
Correct |
6 ms |
9856 KB |
Output is correct |
5 |
Correct |
6 ms |
9856 KB |
Output is correct |
6 |
Correct |
7 ms |
10496 KB |
Output is correct |
7 |
Correct |
7 ms |
10496 KB |
Output is correct |
8 |
Correct |
8 ms |
10496 KB |
Output is correct |
9 |
Correct |
10 ms |
10368 KB |
Output is correct |
10 |
Correct |
10 ms |
10368 KB |
Output is correct |
11 |
Correct |
10 ms |
10496 KB |
Output is correct |
12 |
Correct |
7 ms |
10368 KB |
Output is correct |
13 |
Correct |
9 ms |
10496 KB |
Output is correct |
14 |
Correct |
7 ms |
10368 KB |
Output is correct |
15 |
Correct |
8 ms |
10624 KB |
Output is correct |
16 |
Correct |
9 ms |
10624 KB |
Output is correct |
17 |
Correct |
8 ms |
10496 KB |
Output is correct |
18 |
Correct |
11 ms |
10624 KB |
Output is correct |
19 |
Correct |
9 ms |
10496 KB |
Output is correct |
20 |
Correct |
11 ms |
10368 KB |
Output is correct |
21 |
Correct |
8 ms |
10368 KB |
Output is correct |
22 |
Correct |
6 ms |
9856 KB |
Output is correct |
23 |
Correct |
5 ms |
9856 KB |
Output is correct |
24 |
Correct |
8 ms |
10752 KB |
Output is correct |
25 |
Correct |
9 ms |
10752 KB |
Output is correct |
26 |
Correct |
8 ms |
10752 KB |
Output is correct |
27 |
Correct |
6 ms |
9856 KB |
Output is correct |
28 |
Correct |
7 ms |
10496 KB |
Output is correct |
29 |
Correct |
6 ms |
10496 KB |
Output is correct |
30 |
Correct |
7 ms |
10368 KB |
Output is correct |
31 |
Correct |
7 ms |
10496 KB |
Output is correct |
32 |
Correct |
7 ms |
10368 KB |
Output is correct |
33 |
Correct |
73 ms |
42732 KB |
Output is correct |
34 |
Correct |
77 ms |
42732 KB |
Output is correct |
35 |
Correct |
7 ms |
10752 KB |
Output is correct |
36 |
Correct |
61 ms |
34884 KB |
Output is correct |
37 |
Correct |
61 ms |
34984 KB |
Output is correct |
38 |
Correct |
77 ms |
29836 KB |
Output is correct |
39 |
Correct |
70 ms |
36204 KB |
Output is correct |
40 |
Correct |
66 ms |
30316 KB |
Output is correct |
41 |
Correct |
71 ms |
29936 KB |
Output is correct |
42 |
Correct |
72 ms |
36204 KB |
Output is correct |
43 |
Correct |
98 ms |
30576 KB |
Output is correct |
44 |
Correct |
69 ms |
39152 KB |
Output is correct |
45 |
Correct |
69 ms |
34160 KB |
Output is correct |
46 |
Correct |
66 ms |
33780 KB |
Output is correct |
47 |
Correct |
72 ms |
33648 KB |
Output is correct |
48 |
Correct |
75 ms |
33776 KB |
Output is correct |
49 |
Correct |
69 ms |
33136 KB |
Output is correct |
50 |
Correct |
65 ms |
33524 KB |
Output is correct |
51 |
Correct |
184 ms |
47304 KB |
Output is correct |
52 |
Correct |
217 ms |
47580 KB |
Output is correct |
53 |
Correct |
146 ms |
45272 KB |
Output is correct |
54 |
Correct |
86 ms |
35480 KB |
Output is correct |
55 |
Correct |
80 ms |
35480 KB |
Output is correct |
56 |
Correct |
145 ms |
37812 KB |
Output is correct |
57 |
Correct |
146 ms |
31644 KB |
Output is correct |
58 |
Correct |
84 ms |
29804 KB |
Output is correct |
59 |
Correct |
231 ms |
34752 KB |
Output is correct |
60 |
Correct |
195 ms |
32028 KB |
Output is correct |
61 |
Correct |
195 ms |
39620 KB |
Output is correct |
62 |
Correct |
143 ms |
31912 KB |
Output is correct |
63 |
Correct |
116 ms |
40808 KB |
Output is correct |
64 |
Correct |
111 ms |
35320 KB |
Output is correct |
65 |
Correct |
83 ms |
34668 KB |
Output is correct |
66 |
Correct |
87 ms |
35680 KB |
Output is correct |
67 |
Correct |
98 ms |
35448 KB |
Output is correct |
68 |
Correct |
110 ms |
34656 KB |
Output is correct |
69 |
Correct |
130 ms |
37308 KB |
Output is correct |
70 |
Correct |
71 ms |
21900 KB |
Output is correct |
71 |
Correct |
120 ms |
35636 KB |
Output is correct |